Psychology principle / performance psychology

Yerkes-Dodson Law

Aim for enough pressure to stay alert, but not so much that it disrupts thinking, learning, or control.

Popularity

Usefulness

Aliases

Yerkes-Dodson effect / inverted-U hypothesis / arousal-performance curve

Domains

Experimental psychology / cognitive psychology / learning theory / stress and performance / education / workplace performance / sport psychology

Definition

The Yerkes-Dodson Law states that performance tends to improve as arousal or motivation increases, but only up to an optimal point; beyond that point, further arousal can reduce performance. The common modern version is usually shown as an inverted-U relationship between arousal and performance. (dictionary-apa-org.libdata2015.hilbert.edu)

Too little arousal may lead to low energy, low attention, or weak motivation.
Moderate arousal can improve focus, effort, and learning.
Excessive arousal may create stress, anxiety, distraction, or impaired judgment.
The optimal arousal level depends on task difficulty: difficult or unfamiliar tasks usually require lower arousal than simple or well-practiced tasks. (PMC)

For simple tasks, higher arousal may continue to help performance for longer.
For complex tasks, high arousal can harm attention, memory, and problem-solving.
The original 1908 study used mice learning discrimination tasks under different strengths of electrical stimulus; Yerkes and Dodson concluded that the relation between stimulus strength and learning speed depends on task difficulty. (Psych Classics)

A developer preparing for a production deployment may perform best with enough pressure to stay alert and careful. If pressure becomes too high, they may overlook checks, panic, or make avoidable mistakes.

Example: No verified single famous example found.
Why it fits this rule: Common examples such as exams, sports competitions, public speaking, or workplace deadlines are useful illustrations, but they are usually generalized teaching examples rather than one clearly verified historical case.
Verification status: Illustrative examples are common; a specific famous verified example is unknown.

Do not treat it as a precise universal formula.
Do not assume “more stress is better” simply because low stress can reduce motivation.
Do not apply the same arousal level to every person or every task.
Do not ignore task difficulty, skill level, fatigue, sleep, health, or environment.
Do not overstate the original 1908 study: the broad inverted-U model is a later simplified interpretation of a narrower animal-learning experiment.

Invented by: Robert M. Yerkes and John D. Dodson
Year of invention: 1908
Country / context of origin: United States; Harvard Psychological Laboratory; experimental study on learning and habit formation in mice. (Wiley Online Library)

The original evidence came from Yerkes and Dodson’s 1908 paper, “The Relation of Strength of Stimulus to Rapidity of Habit-Formation,” published in the Journal of Comparative Neurology and Psychology. (Wiley Online Library)
Later psychology literature generalized the finding into the familiar inverted-U relationship between arousal and performance.
Reviews note that the relationship is more complex than the simple curve suggests: simple tasks and difficult tasks may show different arousal-performance patterns. (PMC)
Modern research continues to discuss inverted-U patterns in arousal, stress, cognition, and memory, but the law should be treated as a useful heuristic rather than a universal biological law. (Cell)

Aim for enough pressure to stay alert, but not so much that it disrupts thinking, learning, or control.